Thermostat



J. F. 0. HUGE.

THERMOSTAT.

APPLICATION FILED SEPT-1B, 19I6.

Patented J an. 27, 1920.

llllllllllllllllvll rllllllllglllllll llh 31*? M ATTORNEY UNITED JOSEPH F. D. HOGE, OF NEW YORK, N. Y.

THERMOSTAT.

Specification of Letters Patent.

Application filed September 18, 1916. Serial No. 120,642.

To all whom it may concern:

Be it known that I, J OSEPH F. D. Hoes, a citizen of the United States of America, and a resident of New York, county of New York, and State of New York, have invented certain new and useful Improvements in Thermostats, of which the following is a specification.

My invention relates to thermally-actuated circuit-breaking devices of the type commonly termed thermostats, and comprises means whereby thermostats are rendered VBPY'l'ELPlCl in operatlon, and yet are simple, inexpensive, free from liability to mechanical injury, and very reliable.

The objects of my invention are to increase the rapidity or responsiveness of ther mostats; to produce a thermostat which shall be more reliable or certain in its action than former thermostats and to so construct the thermostat that it shall be very durable, free from liability to breakage in handling, packing, shipping, erection, etc, and which shall be simple and inexpensive to construct, and positive in its action.

I will now proceed to describe my invention with reference to the accompanying drawings, and will then point out the novel features in claims.

In said drawings:

Figure 1 shows a side elevation of one form of thermostat embodying my invention.

Fig. 2 a bottom view thereof, and

Fig. 3 a transverse section thereof on the line 33 of Fig. 2.

My improved thermostat is of the type wherein, in the event of the thermostat being heated above a predetermined degree, a member 1s released through the fus-' weight ing of solder-joints and thereby a circuit is opened.

The promptness of operation of such thermostats depends to a very large degree upon the mass of metal to be heated; for if there be considerable metal to be heated, considerable time will elapse before the solder will be heated to the fusing point; for this solder heats no more rapidly than does the metal with which it is in contact or in heat-conducting relation. According to the present invention I have reduced the mass of the metal to be heated, in order that the solder may melt, to a very low degree, by constructing the thermostat of two light spring members, and a'hollow shell, also of very thin metal, containing within it a heat Patented Jan. 27, 1920.

insulated weight mass, such shell being con nected to the said springs by the low melting solder commonly employed in these thermostats. The springs are, of course, connected to a suitable base, but this base is preferably made of material of low heat conductivity; and because of this fact, and because of the fact that the weight mass within the said shell is heat insulated, the only parts to be heated, in addition to the solder, are, the said thin springs, and the said thin shell. This shell is of such construction as to present a very large relative surface area, thereby facilitating the absorption of heat by the parts to be heated.

In the said drawings, 1 designates a base, preferably of material of low heat conductivity, such for example as fiber or porcelain; 22 designate the said springs, preferably of'the U-form shown, and 3 designates the said shell, preferably, though not necessarily, of approximate spherical form. The springs 2 and the shell 3 are connected by small solder-masses 4, the composition of the solder being such as to cause it to melt at some desired and predetermined temperature.

The shell 3 is hollow, and contains within it a weight mass 5, surrounded by heat-insulating and cushioning material 6, such for example, as loose cotton or wool fiber, spunglass fiber, mineral wool, asbestos, etc. This fibrous packing material is employed for two principal purposes; viz., to reduce to a minimum 'COHCi'LlCtlOIl of heat from the shell 3 to said weight mass, and also to reduce the impact of said shell when, after detachment from the springs 2 it strikes some object in falling. While in general, it is not probable that anything would be harmed by the fall upon it inside, might fall upon crockery or something of the sort, and do injury thereto; unless the fall be cushioned. Now it is clear that the mass of the shell 3 itself is so small that the shell itself is not apt to do injury when it strikes an object; the more so as the metal of this shell is very thin, so that if such shell strikes a solid object with any c'onsid erable force, it :will be apt to crush, so cushioning the impact. Of course the weight mass 5 falls with the shell; but because of the cushioning material 6, when the shell strikes an object, the stoppage of the weight mass is retarded or cushioned, so greatly reof the shell 3 with the weight mass yet it might happen that this 'shell independent of any spring action.

ducing the impact of the blow. However, the principal reason for the employment of the cushioning material is to substantially eliminate the weight mass as a factor retarding the heating up of the shell, solder and springs.

The spherical form of the shell 3 is further desirable, since it substantially insures the operation of the thermostat,upon the fusion of the solder, in whatever position the thermostat be placed. Preferably, of course, the thermostat is placed with its base up and shell 3 down, as indicated in Fig. 1; but the thermostat may be placed in various other positions, for example, with its base inclined or vertical, and still, upon fusion of the solder, the shell 3 will fall away from the springs 2, so opening the circuit of which those springs form terminals.

Solder of low melting point, such as is employed in thermostats, though quite strong, is also brittle, and in the past, fusible joint thermostats have frequently been rendered inoperative through breakage of a solder connection, due to careless handling or some mechanical injury received in erection, or otherwise. To reduce this liability to mechanical injury to a minimum, I preferably make the springs 2 of U-form, and so proportioned that the shell 3 is supported clear of the base 1. The flexible, the shell 3 can yield in any direction to jar or vibration, to force applied in handling, or to contact with tools during erection. It is thus possible to handle the thermostatwithout particular care, to ship it without careful packing, and to erect it without the exercise of special precautions against breakage of the solder joints.

As will be apparent from the foregoing, normally there is a circuit path through the thermostat from the one spring 2 through the shell 3 to the other spring 2. In case of a fire occurring within thevicinity of the thermostat, the solder masses 4 will melt, releasing the ball or shell 3, which will then drop clear of the springs 2, opening this said circuit.

Many prior thermostats have afforded undesirable refuges for insects; and it will be noticed that the design of my thermostat is such that it provides no such refuge. Many prior thermostats have been so constructed' that paint or whitewash if care lessly applied to them, might interfere with their operation; but such is not the case with my present thermostat. Furthermore, mythermostat is not dependent for its operation upon spring action; the 'springs2' are mere 'supports for the weight 3, and inthe event of the solder masses 4: melting, this weight 3 will drop clear of the springs 2, The

springs being very 'tlOIl.

What I claim is: I

1. A thermostat comprising a detachable member, supporting means therefor, comprising a fusible connection, and a weight mass carried by such detachable member but heat insulated therefrom.

2. A thermostat comprising a hollow con tainer, a weight mass therein, heat insulating material surrounding said weight mass and insulating the same from said container, and a support for such container comprising a fusible joint.

3. A thermostat comprising in combination a closed hollow shell of thin material of high heat conductivity, a weight mass within such shell, heat insulating material surrounding such weight mass and insulating the same from said shell, and supporting means for said shell comprising a fusible joint.

4:. A thermostat comprising a heat-absorbing member and a weight mass, the said heat absorbing member being of relatively small mass and large surface area, the said weight mass being carried by such heat absorbing member, in such manner as to reduce largely transmission of heat from such heat absorbing member to such weight mass, and a support for such heat absorbing member comprising a fusible joint.

5. A thermostat comprising in combina tion a weight, two U-springs supporting that weight, and fusible joints connectingsuch U-springs to said weight.

6. A thermostat comprising in combina' tion a separable heat absorbing member consisting of a hollow shell of thin material of high heat conductivity, and supporting means for said shell comprising a fusible joint, said shell arranged to fall away upon the fusion of such joint, the construction being such that because of the thinness of l/Vitness'e's: M. MA LE,

Pant FRANKE;

JOSEPH F5 D. HUGE, 

